What is Aspartame?
Aspartame is a low-calorie sweetener that has been used for decades as a way to lower one’s intake of added sugars while still providing satisfaction from enjoying something sweet. Aspartame is about 200 times sweeter than sugar, and as such only a small amount of the sweetener is needed to match the sweetness provided by sugar. In tabletop packets and prepared foods and beverages, aspartame is often blended with other sweeteners or food components to minimize bitter flavors and enhance overall taste.
Aspartame consists of two amino acids—aspartic acid and phenylalanine. When ingested, aspartame is broken down into these amino acids for use in protein synthesis and metabolism. In addition to aspartic acid and phenylalanine, what is aspartame digestion also yields a small amount of methanol, a compound that is naturally found in foods like fruits and vegetables and their juices. The amount of methanol resulting from consuming an aspartame-sweetened beverage is about five to six times less than that resulting from the same volume of tomato juice.
Aspartame can be used as an ingredient in beverages (such as diet sodas, light or low-sugar juices and flavored waters), dairy products (such as light yogurt and low-fat flavored milk), nutrition bars, desserts (such as sugar-free puddings and gelatins, light ice cream and popsicles), chewing gum, sauces, syrups and condiments. Aspartame is also found in several types of low-calorie tabletop sweeteners. The most common brand of aspartame tabletop sweetener in the U.S. is Equal?. Brands outside the U.S. include Canderel(found in Europe) and Pal Sweet(found in Asia). In addition, some prescription and over-the-counter medications and chewable vitamins may contain aspartame to increase their palatability. Aspartame is not well-suited for use in foods that require baking for a long time because prolonged exposure to high temperatures can cause it to lose its sweetness.

Is Aspartame safe to consume?
Yes. Aspartame is one of the most exhaustively studied ingredients in the human food supply, with more than 200 studies supporting its safety. The U.S. Food and Drug Administration (FDA) approved its use in dry foods in 1981, in carbonated beverages in 1983 and as a general-purpose sweetener in 1996. Leading global health authorities such as the European Food Safety Authority (EFSA) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) conduct scientific risk assessments and safety evaluations of food additives and have concluded that aspartame is safe for its intended uses.2,3 Based on these conclusions and other independent reviews, government regulators around the world, including Japan’s Ministry of Health, Labor, and Welfare; Food Standards Australia New Zealand; Health Canada; and the U.S. FDA permit the use of what is aspartame.
The FDA has established an acceptable daily intake (ADI) for aspartame of 50 milligrams per kilogram of body weight (mg/kg) per day. The EFSA has established a slightly lower ADI of 40 mg/kg per day. The ADI represents an amount 100 times less than the quantity of aspartame found to achieve a no-observed-adverse-effect-level (NOAEL) in toxicology studies. The ADI is a conservative number that the vast majority of people will not reach. Using the ADI established by the FDA, a person weighing 150 pounds (68 kg) would exceed the ADI (3,400 mg of aspartame) if consuming more than an average of 19 cans of diet soda or more than 85 individual packets of aspartame every day over the course of their lifetime. In people who report consuming aspartame, the estimated average intake is 4.9 mg/kg per day, which is less than 10 percent of the FDA’s ADI. For those in the 95th percentile of aspartame consumption, intake is estimated at 13.3 mg/kg per day—still far below the FDA ADI. Globally, aspartame intake also remains well below the FDA and EFSA ADIs. A 2018 study noted that only in rare instances did individuals exceed more than 20 percent of the ADI, even in the highest-consuming groups.5 For more on how ADIs are set, see the “What is an ADI?” sidebar. Although the safety of aspartame is established for intakes not exceeding the ADI, aspartame intake should be limited by people with phenylketonuria (PKU). PKU is a rare genetic disease that makes an affected person unable to properly metabolize phenylalanine, one of the amino acids found in what is aspartame and many common foods like milk, cheese, nuts and meat. Individuals with PKU need to avoid or restrict their intake of phenylalanine from all sources. All packaged foods and beverages with aspartame as an ingredient are required by the FDA to have a statement on the label informing consumers of phenylalanine’s presence.

What is an ADI?
The acceptable daily intake, or ADI, is the average daily intake over a lifetime that is expected to be safe for human consumption based on significant research.6 It is derived by determining the no-observed-adverse-effect-level, or NOAEL, which is the highest intake level found to have no adverse effects in lifetime studies in animal models, divided by 100.7 Setting the ADI 100 times lower than the upper level found to have no adverse effects in research studies helps ensure that human intakes will be safe.

Can children consume Aspartame?
Yes. Aspartame metabolism is the same in healthy children as it is in healthy adults. The EFSA, FDA and JECFA have concluded that aspartame is safe for adults and children to consume within the ADI. Just like with adults, the only exception is for children with PKU who need to avoid or restrict their intake of phenylalanine.
Foods and beverages sweetened with aspartame can add sweetness without contributing to increased calorie intake, added sugars intake or risk of dental caries. With a focus on reducing consumption of added sugars in recent decades, the prevalence of daily consumption of low-calorie sweeteners among children and adults has increased since 2000.8 Just like intake among adults, absolute amounts of low-calorie sweeteners consumed by children is considered to be well within acceptable levels. The American Heart Association (AHA) advises against children regularly consuming beverages containing low-calorie sweeteners, instead recommending water and other unsweetened beverages such as plain milk.9 One notable exception in the 2018 AHA science advisory is made for children with diabetes, whose blood glucose management may benefit by consuming low-calorie-sweetened beverages in place of sugar-sweetened varieties. Citing an absence of data, the 2019 policy statement from the American Academy of Pediatrics does not provide advice on children under two years of age consuming foods or beverages that contain low-calorie sweeteners.